Dividers.



N0.754,9oe. y y PATENTBD MAR.15,1904.

T. R. SKINNBR.

DIVIDBRS.

APPLICATION FILED MAR. 12, 1903. EBNEWED FEB. 8. 1904.

N0 MODEL.

e UNTTED STATES Patented March I5, `1904i PATENT OEETCE.

TERNAY ROBINSON SKINNER, OF DUBOIS, PENNSYLVANIA.

DlpvlDERs.

v' SPECIFICATION forming part of Letters Patent N o. 754,906, dated March 15, 1904.

Application filed March 12, 1903. Renewed ebruary 8, 1904. Serial No. 192,714. (No model.)

To all whom it 19m/y concern:

Be it known that I, TERNAY ROBINSON SKIN-r NER, a citizen of the United States, residing at Dubois, in the county of Olearlield and State of Pennsylvania, have invented certain new and useful Improvements in Dividers; and I do declare the follow-ing to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in dividers.

The object of the invention is to provide an improved means for automatically adjusting the legs of the same to enable the instrument to be used for drawing volutes, a further object being to produce an instrument of this character which will be simple in construction, inexpensive, and well adapted to the use for which it is designed.

With these and other objects in view the invention consists in the construction, combination,and arrangement of the parts, as will hereinafter be more fully described and claimed, reference being had to the accompanying drawings, in which-- Figure l is a side elevation of a pair of dividers embodying my invention. Fig. 2 is a vertical sectional View through the head and upper portion of the same on an enlarged scale.

In the drawings, l denotes the pivoted head, and l denotes the integral leg member of the dividers. 2 denotes the adjustable leg member of the same, and in the lower ends of said legs are formed screw-threaded sockets for the reception of the threaded Shanks of different forms'of points. l

The movable leg 2 is formed in two sections-a short upper section 8, which is hinged at its upper inner edge to the leg la, as shown, j and a lower longersection 4. The section 3 vthe tendency of the spring being to normally force the lower ends of the leg members l and 2 apart. n

Upon the lower end of the leg 2 is attached a double point l0, the office of the same being to hold the lower section 4 of the leg 2 fxedly upon the drawing-paper or surface, so that as the head 1, the nut 3 of the leg 2, and leg l are rotated the nut 3 will be screwed olf of the screw member 7 of the section 4, thereby permitting the spring 9 to force the legs apart and gradually increase the radius of the curve A described by the leg l, thus forming a volute or spiral line upon the paper or drawing-surface.

When it is desired to use the instrumentas an ordinary pair of spring-dividers, the double point 10 is removed and a pen, pencil, or other desired point may be substituted, and after the parts have been adjusted to the desired radius the nut 8 is screwed up and jammed against the lower end of the nut 3, thereby holding the parts in this position.

IVhile I have shown and described a flat leaf-spring for forcing the leg members apart, a coiled spring may be substituted therefor to serve the same purpose.

From the foregoing description, taken in connection with the accompanying drawings, the construction and operation of the invention will be readily understood without requiring a more extended explanation.

Various changes in the form, proportion, and the minor details of construction-may be resorted to without departing from the principle or sacrificing any of the advantages of this invention.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-d TOO l. An instrument of the class described, comprising a leg, a nut pivoted thereto, and a leg having a screw member engaging the nut and bearing against the iirst-mentioned leg, to move the legs angularly when the nut is revolved on the screw member, substantially as describech 2.` An instrument of the class described, comprising a leg, a nut pivoted thereto, and a leg having a screw member engaging the nut and bearing against the first-mentioned leg, to move the legs angularly toward each other when the nut is revolved on the screw member, in one direction, and a spring coacting with the nut and screw member, to spread the legs apart when the nut is revolved in the reverse direction, substantially as described.

3. An instrument of the class described, comprising a leg, a nut pivoted thereto, and a leg having a screw member engaging the nut and bearing against the first-mentioned leg, substantially as described.

4. An instrument of the class described,

comprising a leg, a nut pivotedthereto, a leg having a screw member engaging the nut and bearing against the first-mentioned leg, and a spring to spread the legs apart, substantially as described. v

5. An instrument of the class described,

.comprising a leg, a nut pivoted thereto, a 

